Apparatus for treating textile fabrics



Jan. 1, 1952 c. G. HATAY APPARATUS FOR TREATING TEXTILE FABRICS Filed April 28, 1950 Patented Jan. l, 1952 APPARATUS FUR TREATING TEXTILE FABRICS Charles George Hatay, Georgetown, Mass., as-

signor to E-Z Mills, Inc., New York, N. Y., n corporation of New York Application April 28, 1950, Serial No. 158,825

Claims.

l This invention relates to the treatment of textile fabrics, and particularly to an apparatus for relieving internal stresses in fabrics incident to shrink-proofing them.

In my copending application Serial No. 136,958 filed January 5, 1950, I have disclosed a shrink-proofing process, applicable especially to knitted fabrics, which comprises essentially the following steps: (l) The fabric, while completely wetted, is placed in a substantially tensionless and compressionless condition to cause displacement of the fabric fibres by the internal stresses therein, so that these stresses are relieved or eliminated with the rearrangement of the fibres. In this first or de-stressing operation, the fabric is preferably spread under the surface of a water bath so that the weight of the fabric is compensated by its buoyancy, and the friction of the water is applied to the fabric on a surface which is many times greater than the acting surfaces of the rollers of a. conventional spreader. (2) An alternating electric current is passed through the fabric, while thus de-stressed and retaining at least some of the wetting agent, to cause internal heating of the fabric di-electrically until it is substantially freed of the wetting agent by evaporation.

I have found that the combination of these two steps is highly effective for shrink-proofing fabrics, the shrinkage of a test length of knitted cotton fabric, treated by my process, being considerably less than 1% in a subsequent laundering.

For best results in shrink-proofing fabrics according to the above-described process, the mechanical handling of the fabric in the destressing operation should be carefully controlled to avoid heavy external stresses on the fabric. The application of heavy tension to the fabric during this period tends to reduce the shrink-proofing effect, evidently because it distorts the bres from their relaxed positions or forms which they assume in the de-stressing operation and thereby creates inter-nbre, and intra-fibre stresses which remain in the fabric upon completion of the stabilizing or setting" operation.

The present invention, therefore, has for its principal object the provision of an apparatus by which the fabric can be treated expeditiously in a continuous operation to relieve the internal stresses in the fabric, prior to the stabiliz- .ing or "setting operation.

The new apparatus comprises a container for a liquid wetting agent through which the fabric is transported lengthwise in a submerged path by a conveyor which operates to move the fabric under substantially tensionless and compressionless conditions. The apparatus also comprises a spreader located in the container below the surface of the liquid and operable on the submerged fabric to spread it under the liquid surface while leaving the fabric in its relaxed condition. The spreader in its preferred form is stationary and includes an air pipe or other means in the container for introducing air into the liquid below the path of the submerged fabric, and a guide plate immersed in the liquid above the fabric and having a bottom surface which directs the air bubbles laterally of the fabric path so as to spread the fabric against the plate bottom. In thus spreading the fabric while submerged and moving in a relaxed condition through the liquid, the apparatus differs from conventional fabric spreaders wherein the fabric is stressed by rollers or tensioning devices, for example, incident to the spreading operation. The present apparatus not only spreads the fabric without imposing appreciable stresses in it. but also moves the fabric through the liquid in a near stressfree condition because of the fabric being supported by its own buoyancy in the liquid. To increase the de-stressing effect of the apparatus, it may also he provided with an oscillating device submerged in the liquid and engageable with the fabric passing through the container to impart a gentle shaking movement to the fabric.

In the preferred form of the apparatus, the liquid container is in the form of a trough communicating at one end with a receptacle in which the fabric to be de-stressed is placed in a more or less random state. As the fabric moves lengthwise from the receptacle to the trough, the conveyor passes-it over an oscillating air duct which introduces air into the liquid below the fabric. 'I'he oscillating device serves to untangle the fabric during its passage to the trough and also to innate the fabric so that it floats to the surface of the liquid. Minute bubbles of the air tend to adhere to the fibres and thereby provide added buoyancy to the fabric as it moves along its submerged path in the trough. At the discharge end of the trough, the fabric engages an endless belt which is partly submerged in the liquid and operates as part of the conveyor to withdraw the de-stressed fabric from the trough while maintaining it in 3 a substantially tensionless and compressionless condition.

For a better understanding of the invention, reference may be had to the accompanying drawing. in which Fig. l is a longitudinal sectional view of a preferred form of the apparatus;

Fig. 2 is a plan view of the apparatus illustrated in Fig. 1 and Fig. 3 is a sectional view on the line 3-3 in Fig. 1, showing details of the spreader.

Referring to the drawing, the de-stressing apparatus as there shown comprises a. container III in the form of a trough which at one end opens into theupper part of a receptacle or tank II. The opposite end of the trough is closed, as shown at Illa. The tank Il and the trough IB are filled with a, liquid wetting agent, such as water, to the level A (Fig. l) the tank II being provided with a level outlet I2. 'I'he fabric F.

which as illustrated is in the form of an elongated sleeve or tube of knitted cotton fabric, is

placed in a random-twisted condition in the tank II where it is in a completely wetted state and tends to float under the surface A of the water bath. One end of the fabric tube passes over a horizontal duct or pipe I3 having holes I3a spaced along the pipe between flanges or guides I 3b. The pipe I3 is supported on an oscillating arm or pendulum Il which is hollow and is connected to a source of compressed air (not shown), whereby air is blown continuously through the holes IIa in the upper surface of the pipe I3. In this way, the fabric tube is lnflated, as shown at F', by the air from the oscillating pipe I3. 'I'he air is more or less con'ned between the pipe I3 and a pair of rollers I5 mounted in the opening between trough III and tank I I, although some of the air will continually escape through the mesh of the fabric as it passes to the rollers I5. Thus, the inated part F' of the fabric tube will float on the surface A of the bath, and this floating action, in combination with the oscillations of the pipe I3, serves to untangle the fabric tube as it is drawn out of the tank Il. The oscillating pipe I3 not only serves as a fabric untangling device but also to give the fabric passing through the trough Il an added buoyancy due to minute air bubbles adhering to the fabric fibres.

From the rollers I 5, the fabric passes to a spreader which comprises a horizontal guide plate I6 extending across the trough I0 from one side to the other. The plate I6 is disposed below the surface A of the bath but above the path of the fabric F, and It is slightly bowed downward so that the lower face of the plate slants upward toward its side edges. The plate I6 is made of a water repellent, highly polished material, preferably a transparent plastic material, and is provided along its sides with air vents Isa. A compressed air pipe I1 has a horizontal section I1a extending longitudinally of the trough under the central portion of the curved plate I6, the horizontal pipe section IIa being provided with holes I'Ib spaced along the length of the pipe. The fabric F passes below the plate I6, so that air bubbles from the pipe Ila rise to the fabric at the central or lowermost portion of the plate and thus urges the fabric against the bottom surface of the plate. The plate I6 is imperforate except at its sides, and since the plate bottom slants from pipe I'Ia upwardly and outwardly toward the edges of the fabric path. the air bub- 4 through and along the fabric under the plate, the bubbles finally escaping through the side openings lia. In this way, the bubbles act to spread the fabric against the lower face of the plate I6, the highly polished surface of which serves to reduce the friction tending to oppose the spreading of the fabric by the bubble accion.

The fabric from the spreader IB-I1 passes under a roller I9, overv a roller 20, and then under a roller 2l, these rollers forming part of a conveyor for the fabric and extending transversely between the sides of the trough and below the surface A of the liquid. The intermediate roller 2l is driven by a belt 22 from a squirrel-cage electric motor 2l. Thebelt 22 is arranged to provide a continuous slippage between the belt and the driving motor 23; but as the fabric is pulled along the trough III, the transport roller 2II eects an additional pull on the fabric,y the force of this pull being substantially constant due to the slippage between the belt 22 and the motor 23.

The fabric F passes from the transport rollers I9, 20, 2i to a second spreader comprising a plate 2l and an underlying perforated air pipe 25a, which are similar to the parts I6 and Ila, respectively, of the first air spreader.

From the second air spreader 2l, 25a, the fabric passes between a pair of rollers 21 to a shaker or oscillating device comprising a pair of rollers 28 and 28a mounted on a carriage 29 suspended on one end of a flexible arm 30, the other end of the arm being mounted on a support 4I. The arm 3l! rests upon an eccentric l2 which is rotated by a suitable power source (not shown). As the fabric passes between the rollers 28 and 28a, it is subjected to a gentle shaking action below the surface of the bath by the vertical reciprocation imparted to the rollers through the eccentric 32. This oscillatory movement of the fabric, against the friction of the water, facilitates release of the internal stresses in the fabric fibres.

An endless belt 3l, forming part of the fabric conveyor, is disposed in the trough I0 in front of the shaker device and receives the fabric after the shaking action. The belt 33 is mounted on a series of rollers 3l, lla, 34h, c and 34d. The fabric from the shaker device moves upon the endless belt 33 between the latter and an idler roll It. The endless belt is driven from a suitable power source (not shown) by a drive belt 38 extending around a pulley'l on one end of the roller 3|.

At opposite sides of the tank II) are vertical supports 25 having vertical slots 39a which receive removable studs 46a at the ends of a hollow perforated mandrel Il. The fabric from the endless belt is wound around the mandrel 40 to form a coll Il. The mandrel Il is not driven, but the coil 4l is caused to turn by friction on the endless belt 3l, the coil being supported by the underlying rollers 34e and 34d over which the endless belt extends. As the diameter of the coil increases, due to winding of additional fabric on the coil, the studs 40a of the mandrel slide upwardly in the slots 39a of the supports 3S. A squeeze roller 42, which is provided with a semirigid rubber surface, has studs 42a disposed in the slots 38a and rests upon the upper surface of the fabric coil 4I. The squeeze roll 42 rides upwardly in the guide slots 39a as the mandrel 40 rises from the belt 33 and the underlying rollers 34e and 34d. due to enlargement of coil 4I as the winding proceeds. If desired, the weight bles from the pipe IIa are directed laterally 15 ofthe roller l2 may be supplemented by weights 'trough under near tensionless conditions.

(notshown) mounted on the studs 42a, and the along the trough is stopped.

e In the operation of the de-stressing apparatus, the fabric tube is moved slowly along the trough I due to the pull imparted to the fabric bythe roller 2U and the endless `belt 33. Sincethe mandrel 40 is not positively driven, the apparatus avoids any heavy tension on the fabric as it is drawn through the liquid. The pulling of the fabric by the endless belt 33 acting on the bottom of the'coil4l, and by the transport roll 20, may be supplemented by similartransport rolls located in othery parts of the trough l0, so as to provide,

a uniform movement o f the fabric along the By air-spreading the fabric between the curved plates I6-24 and the compressed air pipes Ila- 25a. the fabric is supported in a flattened condition under the surface of the liquid by the buoyancy of the fabric in the liquid, whereby the fabric is placed under a substantially compressionless and tensionless condition while completely wetted. Because of the absence of heavy come pression rollers or heavy tensioning of the fabric while it is moved through the liquid and then wound on the mandrel 40, the fabric bres remain inthe relaxed positions to which they were displaced by the treatment in the trough I0, whereby the fabric coil 4| is substantially de-stressed.

The trough I0 is provided at the sides with adjustable arms 44 which carry depending guides` 44a engageable with the side edges of the fabric tube F as it moves along the trough. Similar adjustable guides (not shown)u may be arranged at other parts of the trough to guide the fabric in its movement.

As disclosed in my copending application previously identified, the shrink-proofing` process is completed by passing a high frequency alternating current through the de-stressed fabric F, as by transferring the hollow.mandred 40 to a di'- electrie heater and utilizing the mandrel as an electrode and alsoas a duct for blowing preheated air through the fabric coil during the dielectric heatin'g: However, the de-stressed fabric withdrawn from the trough I0 may be passed continuously through the field of the high frequency current, so that the process is entirely continuous.`r

I claim:

l. Apparatus forrelieving internal stresses in a length of textile fabric, which comprises a container for a liquid wetting agent, a conveyor for moving the fabric lengthwise through the liquid in a submerged path under substantially tensionless and compressionless conditions, a guide plate located in the container below the liquid surface but above said path, and means for introducing air into the container below said path to urge the fabric upward against the guide plate and thereby spread the fabric.

2. Apparatus for relievinginternal stresses in a length of textile fabric, which comprises a container for a liquid wetting agent, a conveyor for moving the fabric lengthwise through the liquid in a submerged path under substantially tensionless and compressionless conditions, a guide plate located in the container below the liquid surface but above said path, the guide plate being generally horizontal and imperforate except forair vvents adiacent the edge portions of said path, and means for introducing airinto the container below the plate and between said edge portions, whereby movement of the air through the liquid from said means to the vents acts to. spread the fabric against the, bottom of the guide plate.

3.'Apparatus for relieving internal stresses in a length of textile fabric, which comprises a container for a liquid wetting agent, a conveyor for moving the fabric lengthwise through the liquid in a submerged path under substantially ten-v sionless and compressionless conditions, means for introducing air into the container below said path, Ato urge the fabric upward in the liquid, and a guide plate immersed in the liquid above said means and path and operable to direct the air from said means laterallyof the fabric path to spread the fabric against the bottom of the plate. I

4. Apparatus for relieving internal stresses in a length of textile fabric, which comprises a container for a liquid wetting agent, a conveyorfor moving the fabric lengthwise through the liquid in a submerged path under substantially tensionlessand compressionless conditions, means for introducing air into the container below said path, to urge the fabric upward in the liquid, said means being located between the opposite edge portions of the fabric path, and a generally horizontal guide 'plate immersed in the liquid above said means and path and extending continuously from one edge portion of the path to its other edge portion, the bottom of the plate slanting downward from said edge portions toward said means, whereby the plate directs the air from said means laterally of the fabric path to spread the fabric against the bottom of the plate.

,5. Apparatus for relieving internal stresses in. a length of textile fabric, which comprises a container for a liquid wetting agent, a conveyor for moving the fabric lengthwise through the liquid in a submerged path under substantially tensionless and compressionless conditions, means for introducing air into the container below said path, 'to urge the fabric upward in the liquid, and a guide plate immersed in the 'liquid above said means and path and having a said means laterally of the fabric path and thereby spread the plate.

6. Apparatus for relieving internal stresses in a length of textile fabric, which comprises a container for a liquid wetting agent, a conveyor for moving the fabric lengthwise through the liquid in a submerged path under substantially tensionless and compressionless conditions, an air pipe in the container below 'said path and extending lengthwise of said path between its edge portions, the pipe having air outlet openings spaced along said path, and a guide plate immersed in the liquid above said path and pipe and having a bottom surface slanting upwardly and outwardly from the pipe toward at least one edge portion of the fabric path, to direct the air from the pipe openings laterally of the fabric path and thereby spread the fabric against the bottom of the plate.

7. Apparatus for relieving internal stresses in a length of textile fabric, which comprises a trough for a liquid wetting agent, a receptacle communicating with one end of the trough and. adapted to receive the fabric, a conveyor for fabric against the bottom of the moving the fabric lengthwise from the receptacle path. under substantially tensionless and cornpressionless conditions, to the other end of the trough, a spreader located intermediate the ends of the trough below the surface of the liquid adjacent said path and operable on the submerged fabric to spread the same under said surface, and a fabric untangling device operable on the fabric passing from the receptacle to the trough.

8. Apparatus for relieving internal stresses in a length of textile fabric, which comprises a trough for a liquid wetting agent, a receptacle communicating with one end of the trough and adapted to receive the fabric, a conveyor for moving the fabric lengthwise from the receptacle through the liquid in the trough in a submerged path, under substantially tensionless and compressionless conditions, to the other end of the:

` fabric passing from the receptacle to the trough.

9. Apparatus according to claim 7, in which said untangling device is an oscillating member disposed in the receptacle.

10. Apparatus for relieving internal stresses in a length of textile fabric, which comprises a 8 trough for a 'liquid wetting agent, a receptacle communicating with one end of the trough and adapted to receive the fabric, a conveyor for moving the fabric lengthwise from the receptacle through the liquid in the trough in a submerged path, under substantially tensionless and compressionless conditions, to the other end of the trough, a spreader located intermediate the ends of the trough below the surface of the .liquid adjacent said path and operable on the submerged fabric to spread the same under said surface, and an oscillatable air duct engageable with the underside of the fabric passing from the receptacle to the trough.

CHARLES GEORGE HATAY.

REFERENCES CITED The following references are of record inthe le of this patent:

UNITED STATES PATENTS Number Name Date 557,468 Woodman Mar. 31, 1896 637,685 Vockler Nov. 21, 1899 1,912,724 n Remington June 6, 1933 1,935,526 Spuhr Nov. 14, 1933 2,064,512 Wilson et al Dec. 15, 1936 2,344,557 Mann et al. Mar. 21, 1944 f 2,441,308 Bond May 11, 1948 2,474,717 Belcher June 28, 1949 

